Answer
$\sqrt{3}/3$
Work Step by Step
When taking a square root of a fraction, we take the square root of the numerator (top of the fraction) and denominator (bottom of the fraction) separately. The square root of 36 is 6, and there is no integer square root of 12, giving us the expression of $\sqrt{12}/6$. However, we know that 4, which is a perfect square, is a factor of 12. Thus, we can simplify:
$\sqrt{4}\sqrt{3}/6=2\sqrt{3}/6=\sqrt{3}/3$